The presence of airborne particulate matter poses a serious hazard with respect to both the environment in general and personal health and safety in particular. For example, wind errosion of mine trailings has seriously disrupted normal living in the vicinity of certain mining localities. This dust contaminates food, potable water sources and fertile soils and, in some instances, interferes with the driving of automobiles on adjacent highways. In addition, airborne particles from any given source are often inhaled, resulting in serious respiratory ailments such as silicosis.
Common industrial sources of such dust has been categorized as open operations, leaks and spills, storage and disposal, and in completely controlled points and/or housekeeping. The iron and steel industries are replete with examples of these enumerated categories. For example, steel mills have been ordered to install systems to control the dust, smoke, and sparks from electrical furnaces associated therewith. These particles emanated from what would best be categorized as the "open operations" noted above. The abovenoted disposal and storage source of dust is exemplified by the facts surrounding the use of the steel mill open hearth precipitator which has an electrostatic precipitator to control dust emissions. The dust removed by the electrostatic precipitator is typically collected in hoppers and periodically dumped in essentially closed containers known as "collecting". Despite the fact that connecting hoses are extended between the hopper and collecting fan, considerable dust emissions occur during material transfer. If the electrostatically removed particulate matter is to be used as landfill, several dust emissions can occur during the dumping and natural winds have been observed creating great dust clouds at the particular landfill site. The transportation of particulates along conveyor belts and the dumping of the particulates therefrom also create fugitive dust emission problems of the "transportation and disposal" source type. The "leaks and spills" and "poor housekeeping" sources of dust emissions are seen to be self-explanatory and, thus, further explanation of these categories is considered unwarranted.
In this light, certain chemical additives have been developed which are adapted to wet the troublesome dust, and to thereby control the dissemination thereof into the atmosphere. One such chemical compound is disclosed in U.S. Pat. No. 4,171,276 (Brehm)--of common assignment herewith.
Although the prior art located as a result of a preliminary. examination directed toward this invention did not uncover any devices which are specifically adapted to the problem of measuring the wetting efficacy of dust control chemical additives, several of the located patents may be of interest. For instance, in U.S. Pat. No. 2,217,175 (Ledbetter) a method of testing drilling fluid is disclosed wherein mud is introduced into a ring member and the ring and mud are placed atop filter paper. The time required after the introduction of the mud into the ring for absorbed water to make its appearance at the outer edge of the filter paper is noted and used to evaluate formation penetration characteristics of the mud.
In U.S. Pat. No. 3,572,090 (Graham et al) an apparatus and method for testing the absorbancy characteristics of paperboard is disclosed. In accordance with the disclosed apparatus, a chamber is provided to contain a predetermined amount of liquid. Means for supplying liquid to the chamber are provided as well as are means for maintaining a sample of the paperboard to be tested with only a cut edge thereof exposed to the liquid in the chamber. Further, photoelectric means and a calibrated capillary tube are provided to measure the rate of which the predetermined amount of liquid changes as liquid is absorbed into the cut paperboard edge.
U.S. Pat. No. 3,952,584 (Lichstein) discloses a device for the measurement of absorbancy characteristics of absorbant structures. The disclosed device comprises a liquid reservoir having an opening at its bottom and a closed air-tight top. Further, a plate or the like is provided in communication with the sample to be tested. Liquid is drawn from the reservoir via capillary action, and the wetting rate of the sample is measured as the partial capacity or the volume of liquid absorbed as a function of time.
Other patents located during the preliminary search, which may be of interest, consist of U.S. Pat. No. 2,121,423 (Colbeth); U.S. Pat. No. 2,651,936 (Marnon et al); U.S. Pat. No. 3,067,622 (Ballestra) and U.S. Pat. No. 3,605,501 (Chenevert).
Despite the efforts of the prior art, there remains a need for a device which can measure the wetting efficacy of certain chemical additives which are adapted to wet and thereby control the dissemination of dust particles in the atmosphere. There is a more specific need in the art for such a device which is portable, and can be readily assembled at a test site, without need for any power source. There is a more specific need for such a device which is capable of measuring the wetting efficacies of a plurality of chemical additives, in simultaneous manner.
These and other objects are met by the invention described and claimed herein. The invention is herein described in detail in the following detailed description of the invention which should be read in conjunction with the appended drawings.